Grease ram



Oct. 31, 1933. N. F. McNAUGHT 1,932,796

GREASE HAM Filed May 18, 1931 2: II T1] 2 11:11" i aw/y @m'xw, @M jf is:

Patented Oct. 31, 1933 1,932,793 H GRESERAll/I V Norris F. McNaught, Chicago, 111., assignor to.

Bare Metal ,Products Company, a corporation of Illinois Application May 18, 1931. Serial No. 538,1381. I

2 Claimaf, (crisp-105 1 V My invention relates to a grease ram, and isparticularly concerned with improved means for braking and limiting'outwa'rd movement ofthe U V U V v ,is provided with an impact head or-janvil' l2 plunger of such a device.

Y Grease rams of the kind to which this invention relates ordinarily'are employed to force fresh grease through bearings when, due to the accumulation of hard grease in the bearings or for other reasons, the ordinary. grease gun will not serve thepurpose. The procedure, in using such a grease ram, is to fill the ram with grease, substitute it for the grease cup or lubricating fitting with which the bearings ordinarily are equipped, and then sharply strike the impact head of the ram a blow with a hammer or other tool to force an adequate supply of grease into the'bearing under very high pressure.

In the accompanying drawing illustrating a preferred embodiment of my invention Fig. l is a view of the grease ram, partly in' elevation and partly in axial section, the extended position of the plunger being illustrated by full lines and its depressed position being indicated by dotted lines;

Fig. 2 is a section taken on the line 2-2 of Fig. l and looking in the direction indicated by the arrows; and

Fig. 3 is a view corresponding to Fig. 2, which may be regarded as taken when the plunger is in the depressed positionindicated by dotted lines in Fig. 1.

Similar characters of reference refer to similar parts throughout the several figures.

In the drawing,- reference numeral 4 indicates f a barrel which, throughout the greater portion of its length, preferably is hexagonal to facilitate its application to and disengagement from an internally threaded passage leading toa bearing on an automotive vehicle or other piece of machinery, i. e. the internally threaded opening into which a grease cup or lubricating nipple ordinarily is threaded. The barrel is provided with an externally threaded nipple 5 affording a passage 6 for the discharge of grease from the barrel bore '7. p v

At its upper end the barrel 4 is provided with a short counterbore coaxial with the main barrel bore 7 to afford an annular compartment 8 housing a brake-detent 9 presently to be discussed in more detail. The annular compartment 8 is .de-- fined by the upper portion of the barrel, the ram plunger 10 and an internally threaded collar 11 which cooperates with external screw threads formed on the upp'erend of the barrel, and is position shown in Fig. I, theinwardlycurving explunger from the full line position of Fig. l.

" Chicago, Ill- I provided with a central aperture through which the ram plunger 10 extends. f

-At its upper'or outer end the ram plunger9 adapted-to be'str'uck by ahammeror'other tool'eo in operating the ram'to force grease into a'clo ed bearing. H p Near its lower or inner end the-plunger lo'is provided with an annulargroovefwhichgenerally' is v-shaped, one wall of this V-shaped groove, 5

indicated at 13, being located in a plane at right angles to the axis of the plunger 10, and the other wall of the groove, indicated at 14, constituting the frustum of a cone having its axis coincident with the axis of the'plunger 10. I j

The brake-dete'nt 9 is in the form of a single piece of spring wire conformed to present an an: nular portion 9a occupying the annular 'compartment 8 to which reference previously was made, the ends 9b, 9'b of thissingle piece of spring wire curving inwardly from the annular. portion 9-a to engage and embrace the plunger 10. l In using theram, the plunger is placed in the dotted line position ofFig. 1 and-the nipple 5 is immersed in a supply of lubricant. The plunger then is 'moved to the full line position of, Fig. l to fill the barrel bore 7 with lubricant. When, on its outward movement, the plunger reaches the tremities 9b, 9b of the brake-detent snap into the annular groove of the plunger, and by their engagementwith the wall 13' of such groove prevent the plunger from being entirely'withdrawn from the barrel. The barrel nipple 5"now is 90, threaded into an opening associated jwiththe bearing'to be lubricated, and the impact head 12 is struck a sharp blowwith a hammer or other suitable tool to depress the plunger and force grease under high pressure through the nipple 5. .When the plunger thus is depressed, the extremi'- ties 9-b, 9--b of the brake-detent rideup the conical wall of the plunger groove onto the cylindrical surface of Jthe plunger.

Normally, when the ram is not in us'e,\the

plunger will occupy the dotted line' position of not prevent outward movement of the plunger. 0

Howevenas previously pointed out, the said extremities 9b, 9-b of thebrake-detent do'act positively to prevent outward movement of the A salient advantage of the particular form of brake-detent herein shown and described is that there is practically no tendency for'the inwardly curvingfextremities 9-b, 9-b thereof to take a set in the positions of Fig. '3, even though the ram; with plunger depressed, may remain unused for many months at a time. Ithas been quite a problem, within my experience, to provide, asimple form of brakec-detent which does not have a tendency to take a set when its plunger engaging parts-are for long periods of time out of the positions which they occupy when cooperating with the-annular groove of the plunger.

Having thus illustrated and described the prel ferred embodiment of my inventiomwhat I claim is new and desire to secure Letters Patent 7 of the United States, is: a r

1. In a grease ram, a barrel adapted for connection with a bearing, a plunger operating in the barrel and projecting from one end thereof, the

nd of thelbarrel from which the plunger projeeps}- .counterbored to provide'an'annular seat,"a collar closely surrounding the plunger and threaded upon the last mentioned end, of ijihe barrel, the saidannular seat,"'collarl;and

plunger defining a detent-brake;compartment, a

-.detent;-brake freely disposed in said ccinpart ment, said detent-brake consisting of a piece of spring wire-conformed to define a circle and hav ing itsends crossing each other and curving in- ZO i wardly from said circleto define an expansible the said conical wall, when the plunger is struck inwardly.

lun'ger, a grooveifor n'ed in the plunger near its within the confinesof said barrel, said detentbrake. beingin the form of a piece or spring wire conformed to define a circle and having its ends "crossing each other and curving inwardly from said circle to definean expansibleplunger e'mbracing oval lying within saidcircle,,,,the, in-

wardlycurving ends of the detent-brakebeing adaptedto ride into engageme'ntwith the abutment; wall to limi the outward movement of the plunger and to be guided outofsaid groove when the plunger is struck inwardly. I i

, INORPUIS F-. NICNAUGHT.

2. Ina grease ram comprising a barrel andia 1111161 end and providing an abutment'wall and eaqdetent-brake;located at the end of the barrel p from which the plunger projects and lying wholly a 

